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Date: Tue, 4 Aug 2015 16:01:37 +0200
Message-ID: <CAMuHMdVi4YTe9Cg5y3dabSoYfcWtG3KfNkfmgZd8TDMMk4Wo+g@mail.gmail.com>
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Dan Carpenter <dan.carpenter@oracle.com>
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Subject: Re: [Ksummit-discuss] [TECH TOPIC] Fix devm_kzalloc, its users,
	or both
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On Tue, Aug 4, 2015 at 2:55 PM, Dan Carpenter <dan.carpenter@oracle.com> wrote:
> Another thing which I have seems fairly common is treating it like
> kmalloc() and calling devm_kfree() manually.  For example, ssp_parse_dt()
>
> drivers/iio/common/ssp_sensors/ssp_dev.c
>    493          return data;
>    494
>    495  err_mcu_reset_gpio:
>    496          devm_gpio_free(dev, data->mcu_reset_gpio);
>    497  err_ap_mcu:
>    498          devm_gpio_free(dev, data->ap_mcu_gpio);
>    499  err_free_pd:
>    500          devm_kfree(dev, data);
>    501          return NULL;
>    502  }

These indeed look superfluous.

In some cases it may legitimate, though, when freeing memory not tied directly
to the lifetime of the device.
Cfr. drivers/media/platform/soc_camera/soc_camera.c, where the operation
may be retried later.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds